Abstract
This work consists of an experimental and numerical study of the behavior and strength of laminated composites subjected to a low velocity/low energy impact. The main objective is to develop a robust model capable of predicting the static and dynamic response of laminated composites, based on accurate experimental observations. Impact tests have been performed using a drop tower instrumented with high-speed cameras to monitor the evolution of damage in real time. The 3D finite element study of impact in explicit dynamics allows to judge the applicability of the failure criteria and the damage evolution methods. Various progressive damage models are implemented to predict the initiation and accumulation of damage in an NCF composite laminate. Cohesive elements are also inserted between adjacent plies to account for inter-ply delamination. In a second step, the model has been validated to reliably simulate the evolution of the mechanisms until failure, under quasi-static loading situations. In this case, the NCF composite is modeled using a unitary constitutive model at mesoscale, and presenting idealized regions of the polymer matrix and impregnated wicks. The idealized unitary model is defined on the basis of data from image analysis. The proposed methodology is generic, using a 3D elemental representation of the part for the global analysis, as well as the non-linearity of the matrix and the local response to the damage.